Title (de)

Title (fr)

Publication

Application

Priority

DE 9900834 W 19990323

DE 19818190 A 19980423

Abstract (en)

[origin: DE19818190A1] The invention relates to a method and a device for contactless measurement of the thickness of transparent materials. The invention aims at reliably providing reflections and thereby measuring values even in the case of not ideally flat measuring objects which are not distorted by wedged walls and tiltings of the measuring objects and which supply plottable reflections to the sensors even in the case of sharply wedged or curved walls despite a limited aperture of the receiving optics. This is achieved in that the light from the luminous areas (11 and 21) is initially collimated and subsequently focused at an incident angle to the surface normal on the surface of the measuring object (1) and both light reflections entering at a front and rear side are further projected to an optoelectronic image resolution sensor (26 and 16), whereby the imaging systems associated with the luminous areas (11 and 21) have an identical structure yet impinge upon the measuring object (1) with opposite optical paths.